By-pass turbojet including a thrust reverser
View Patent ↗A by-pass turbojet including a thrust reverser is disclosed. The thrust reverse includes a deflector device which deflects all or part of the primary stream gas in such a manner that the deflected primary stream gas encounters the secondary stream, thereby reducing the injection speed of the secondary stream in an aft direction, and thus generating the thrust-reversal effect. The secondary stream escapes from the aft end of the nacelle. In the thrust-reversal position, the deflector device is inscribed radially substantially within the section of the primary nozzle cowl at the aft end of the nacelle. Such a thrust reverser is particularly simple in design, inexpensive, and makes it possible to avoid having moving parts present on the outside portion of the nacelle, thus simplifying the design of the turbojet.
1. A by-pass turbojet defining an axis and forward and aft directions, comprising:
a nacelle;
a primary stream passing through a compressor;
a combustion chamber downstream from which the primary stream gas is ejected via a turbine in a primary nozzle cowl;
a secondary stream;
and a thrust reverser, wherein the thrust reverser comprises deflector means suitable, in a thrust-reversal position, for deflecting all or part of the primary stream gas in the vicinity of or downstream from an aft end of the nacelle; such that in the thrust-reversal position, the deflected primary stream gas encounters the secondary stream, thereby reducing the speed of ejection thereof in the aft direction, and thus generating a reverse-thrust effect, with the deflected secondary stream escaping from the aft of a rear end of the nacelle,
wherein the aft end of the nacelle is free of a moving part which moves to the thrust-reversal position from a normal operating position, wherein the outer periphery of the nacelle is constituted by parts that are stationary, and
wherein in the thrust-reversal position, the deflector means are inscribed radially substantially inside the section of the primary nozzle cowl at the aft end of the nacelle.
2. A turbojet according to claim 1 , wherein said deflector means comprise at least one moving structure suitable for moving from the normal position to the thrust-reversal position in which the moving structure deflects all or part of the primary stream gas.
3. A turbojet according to claim 2 , wherein axial thrust along the axis of the turbojet serves to cause the moving structure to pass into the thrust-reversal position.
4. A turbojet according to claim 2 , further comprising a central body about which the primary stream flows; wherein said central body presents a portion of greatest diameter; and wherein in the thrust-reversal position, the moving structure is positioned substantially around said greatest-diameter portion.
5. A turbojet according to claim 4 , wherein the moving structure in the thrust-reversal position is substantially in the form of a ring disposed around said central body to deflect all or part of the primary stream gas.
6. A turbojet according to claim 2 , wherein the movement of the moving structure is movement in translation.
7. A turbojet according to claim 2 , wherein the moving structure comprises the aft portion of the primary nozzle cowl that moves on passing from the normal position to the thrust-reversal position.
8. A turbojet according to claim 1 , wherein the deflector means comprise a bleeder system for bleeding all or part of the primary stream gas, and injectors for injecting the bled gas against the secondary stream.
9. A turbojet according to claim 8 , wherein the bleeder system is suitable for bleeding the primary stream gas upstream from the combustion chamber.
10. A turbojet according to claim 9 , wherein the bleeder system is suitable for bleeding the primary stream gas downstream from the combustion chamber.
11. A turbojet according to claim 8 , wherein the thrust reverser includes one or more moving flaps suitable for being deployed in the primary stream gas annulus in order to deflect the gas.
12. A turbojet according to claim 1 , wherein the deflector means include means for providing protection against high temperatures.
13. A turbojet according to claim 1 , wherein the deflector means further include fins.
14. A turbojet according to claim 1 , wherein the deflector means comprise one or more perforated walls.
15. A turbojet according to claim 1 , wherein the deflector means comprise a perforated box.
16. A turbojet according to claim 2 , further comprising actuators which actuate the moving structure, the actuators being radially disposed between the primary stream and the secondary stream.
17. A turbojet according to claim 8 , wherein the injectors are provided on an aft end of a primary nozzle cowl and the injectors are directed towards the aft of the rear end of the nacelle so as to deflect the secondary stream.
18. A turbojet according to claim 7 , wherein the moving structure includes a set of flaps which are substantially radial and in a shape of a ring placed around a central body of the turbojet, the flaps being disposed on an upstream portion of the aft portion of the primary nozzle cowl so as to intersect and deflect all or part of the primary stream in the thrust-reversal position.
19. A turbojet according to claim 18 , wherein the deflector means includes a plurality of fins extending substantially parallel to the flaps.